When it debuted at Cannes in 2008, Hunger closed to a standing ovation, but not before a number of people had fled. A film of grueling beauty, Hunger, which recounts the 1981 Irish hunger strike, earned the Caméra d’Or at Cannes for first-time director Steve McQueen, a visual artist hitherto known for gallery films under the influence of Andy Warhol. Put simply, there is nothing to prepare you for Hunger. The film is fanatically careful in its depiction of human suffering, exhibiting the same beatific calm as the dazzling Let the Right One In. It also is the most stomach-turningly and gaspingly violent — real flesh-and-bone violence — film in recent memory, as upsetting and powerful as any movie I’ve seen. Not since the curb scene in American History X have I felt so challenged by a film’s total embrace of brutality, although to be clear, Hunger makes American History X look about as fierce as Reading Rainbow.

Hunger has three chapters. In the first, we observe a group of imprisoned IRA members in the Maze, one of Ireland’s most infamous prisons. To achieve the status of political prisoners, the men engage in various protests ranging from the passive (smearing their feces, refusing to be bathed) to the active (head-butting guards), all of which earn them beatings without mercy. In this segment, the film focuses on Davey (Brian Milligan) and Gerry (Liam McMahon), two atrophied cell mates who refuse to wear prison clothing and who receive instructions from their leader, Bobby (Michael Fessbender), via tiny messages passed in chapel. The middle chapter is something of a reprieve, at least on the matter of violence: The 17-minute scene between Bobby and his priest — in which Bobby reveals the plan for the hunger strike while the priest, played by Liam Cunningham, tries in vain to dissuade him — is by far the longest single shot ever filmed, more than doubling Robert Altman’s eight-minute take in the The Player. During the verbal clash, their moral philosophies sizzle and spark; it’s both vital and educational to watch Bobby defend his effort to end British rule in Ireland. The final, haunting section of Hunger is Bobby’s hunger strike, which lasts 66 days.

Much of Hunger has the quality of an elegy, a sincere but distant ode to defiance during a chilling era of history that seems destined to be reenacted for as long as there are repressive regimes to enact them. (I’m thinking of the Russian Gulag, not to mention Guantanamo Bay.) The achievement of Hunger is how personally, how carefully McQueen and his co-writer Enda Walsh treat these men and their limited existence. Hunger lingers for extended stretches on the mopping of hallways, the buzzing of a fly or the removal of excrement from walls. McQueen seems as interested as in passing of time as he is in the prisoners’ assertions of dignity. All of it is powerful; some of it is gratuitous, in particular the fate that befalls one of the prison guards. Or the cavity searches the men undergo in which the same pair of gloves probes their asses and their mouths. I barely made it through Hunger, but days later, I’m glad I did. The film’s methods are exceedingly effective; of its message, I’m less certain. If you recreate the violence of an era with total accuracy, are you doing a service to history or art?